Synchronizing StreamWriter

Also, the "lock" statement will allow you to prevent multiple threads from running the same code simultaneously:

http://msdn2.microsoft.com/en-us/library/c5kehkcz.aspx

I'm not sure it's a good idea to have several threads attempting to write to the same file.

I would suggest creating a class that controls access to that file, implement it as a Singleton (so that there's only one instance of it within your app) and set up a write method in that class to receive the data that is to be written to the file.  The code within the write method should be synchronzied so that only one thread at a time can access it.

Look at the MSDN article on TextWriter.Synchronized:
http://msdn2.microsoft.com/en-us/library/system.io.textwriter.synchronized(VS.71).aspx

Hi.try this code without Using the Thread

using System;
using System.IO;
class Class
{
 static void Main()
 {

  // Write out to text file
  StreamWriter writer = File.CreateText("c:\\me.doc");
  writer.WriteLine("Arshad you are Out of file.");
  writer.Close();

  // Read all lines from text file
  StreamReader reader = File.OpenText("c:\\me.doc");
  string line = reader.ReadLine();
  while (line != null)
  {
     Console.WriteLine(line);
     line = reader.ReadLine();
  }
  reader.Close();

 }
} 

Regards

Arshad Khan